/* * Copyright (C) 2004, 2007-2010, 2011-2012 Synopsys, Inc. (www.synopsys.com) * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License version 2 as * published by the Free Software Foundation. * * Joern Rennecke <joern.rennecke@embecosm.com>: Jan 2012 * -Insn Scheduling improvements to csum core routines. * = csum_fold( ) largely derived from ARM version. * = ip_fast_cum( ) to have module scheduling * -gcc 4.4.x broke networking. Alias analysis needed to be primed. * worked around by adding memory clobber to ip_fast_csum( ) * * vineetg: May 2010 * -Rewrote ip_fast_cscum( ) and csum_fold( ) with fast inline asm */ #ifndef _ASM_ARC_CHECKSUM_H #define _ASM_ARC_CHECKSUM_H /* * Fold a partial checksum * * The 2 swords comprising the 32bit sum are added, any carry to 16th bit * added back and final sword result inverted. */ static inline __sum16 csum_fold(__wsum s) { unsigned r = s << 16 | s >> 16; /* ror */ s = ~s; s -= r; return s >> 16; } /* * This is a version of ip_compute_csum() optimized for IP headers, * which always checksum on 4 octet boundaries. */ static inline __sum16 ip_fast_csum(const void *iph, unsigned int ihl) { const void *ptr = iph; unsigned int tmp, tmp2, sum; __asm__( " ld.ab %0, [%3, 4] \n" " ld.ab %2, [%3, 4] \n" " sub %1, %4, 2 \n" " lsr.f lp_count, %1, 1 \n" " bcc 0f \n" " add.f %0, %0, %2 \n" " ld.ab %2, [%3, 4] \n" "0: lp 1f \n" " ld.ab %1, [%3, 4] \n" " adc.f %0, %0, %2 \n" " ld.ab %2, [%3, 4] \n" " adc.f %0, %0, %1 \n" "1: adc.f %0, %0, %2 \n" " add.cs %0,%0,1 \n" : "=&r"(sum), "=r"(tmp), "=&r"(tmp2), "+&r" (ptr) : "r"(ihl) : "cc", "lp_count", "memory"); return csum_fold(sum); } /* * TCP pseudo Header is 12 bytes: * SA [4], DA [4], zeroes [1], Proto[1], TCP Seg(hdr+data) Len [2] */ static inline __wsum csum_tcpudp_nofold(__be32 saddr, __be32 daddr, __u32 len, __u8 proto, __wsum sum) { __asm__ __volatile__( " add.f %0, %0, %1 \n" " adc.f %0, %0, %2 \n" " adc.f %0, %0, %3 \n" " adc.f %0, %0, %4 \n" " adc %0, %0, 0 \n" : "+&r"(sum) : "r"(saddr), "r"(daddr), #ifdef [31mCONFIG_CPU_BIG_ENDIAN[0m "r"(len), #else "r"(len << 8), #endif "r"(htons(proto)) : "cc"); return sum; } #define csum_fold csum_fold #define ip_fast_csum ip_fast_csum #define csum_tcpudp_nofold csum_tcpudp_nofold #include <asm-generic/checksum.h> #endif /* _ASM_ARC_CHECKSUM_H */ |